Vitamin D status and its predictive factors in pregnancy in 2 Australian populations.

MedLine Citation:

PMID:
21806574
Owner:
NLM
Status:
Publisher

Abstract/OtherAbstract:

Background: High prevalence rates of suboptimal vitamin D levels have been observed in women who are not considered 'at risk'. The effect of behavioural factors such as sun exposure, attire, sunscreen use and vitamin D supplementation on vitamin D levels in pregnancy is unknown. Aim: To determine prevalence and predictive factors of suboptimal vitamin D levels in 2 antenatal clinics in Australia - Campbelltown, NSW and Canberra, ACT. Methods: A cross-sectional study of pregnant women was performed with a survey of demographic and behavioural factors and a mid-pregnancy determination of maternal vitamin D levels. Results: The prevalence of vitamin D deficiency (≤25 nmol/L) and insufficiency (26-50 nmol/L) was 35% in Canberra (n = 100) and 25.7% in Campbelltown (n = 101). The majority of participants with suboptimal D levels had vitamin D insufficiency. Among the vitamin D-deficient women, 38% were Caucasian. Skin exposure was the main behavioural determinant of vitamin D level in pregnancy in univariate analysis. Using pooled data ethnicity, season, BMI and use of vitamin D supplements were the main predictive factors of suboptimal vitamin D. Vitamin D supplementation at 500 IU/day was inadequate to prevent insufficiency. Conclusions: Behavioural factors were not as predictive as ethnicity, season and BMI. As most participants had one of the predictive risk factors for suboptimal vitamin D, a case could be made for universal supplementation with a higher dose of vitamin D in pregnancy and continued targeted screening of the women at highest risk of vitamin D deficiency.

Department of Endocrinology and Diabetes, The Canberra Hospital, Canberra, ACT Department of Endocrinology and Diabetes, Campbelltown Hospital School of Medicine, University of Western Sydney, Campbelltown, NSW Department of Chemical Pathology, The Canberra Hospital Australian National University Medical School The Centre for Advances in Epidemiology and Information Technology, The Canberra Hospital, Canberra, ACT Department of Medicine, Campbelltown Hospital, Campbelltown, NSW, Australia.